Sea Technology

NOV 2017

The industry's recognized authority for design, engineering and application of equipment and services in the global ocean community

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20 st / November 2017 www.sea-technology.com deterministic forecasting system to provide the ship motions that will result from the waves forecasted to impact the ship in the next few minutes. During operation, the generated ocean wave components can then be used as real-time in- puts to the lookup database, with the lookup database pro- viding necessary terms to calculate the resulting forecasts of ship motions. Thus, the lookup database with precalculated values can be used to provide fast determinations of ship motion forecasts. This facilitates the real-time determination of several minutes of ship motion forecasts for each radar scan and each cycle of wave component calculation. Another innovation of the ESMF and FutureWaves effort has been a smart sea-keeping model that is adaptive and self-learning. Through a constant feedback loop of compar- are precalculated through a discretized range of speeds and wave frequencies and directions, yielding a database that characterizes the hydrodynamic forcing to the ship through all relevant operating conditions. Particular values of these forcing functions are obtained through interpolation of val- ues from the database. The approach uses the assumptions of linear sea-keeping theory, where the hydrodynamic forc- ing can be decomposed into the incident wave, diffraction and radiation forces. The precalculated wave-forcing da- tabase allows mapping of the discrete wave components to modal forcing of the ship system. Thus, resultant vessel motions for different courses and speeds can be calculated for the course/speed recommendation model. This lookup database can also be used during operation of the real-time It's easy to search the harshest of environments safely and quickly with a JW Fishers commercial grade ROV. - Pan & tilt front AND rear cameras - LED lighting - Highly portable system - 1,000 foot (300m) depth capability - Many "add-on" options such as a manipulator arm, side cameras, scanning sonar, metal detectors and more! JW Fishers Mfg., Inc. / 1953 County Street / East Taunton MA 02718 USA (800)822-4744 or (508)822-7330 / Email: info@jwfishers.com / www.jwfishers.com Underwater Search Equipment it PAYS to Own Frozen Fish Lake, Plain WA An LCAC approaches MSC's ESD USNS Montford Point, demonstrating skin-to-skin operations, ve- hicle transfer and launch and recovery while at- tached to the LMSR USNS Bob Hope. (Photo Credit: U.S. Navy, Shannon E. Renfroe)

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